FI-6 was a British intelligence agency. They are perhaps best known for having been the former employer of Micromax, who later had many interactions with Excalibur and other Marvel super-heroes.

Most members of FI-6 were not super-heroes like Micromax. Many of members of this organization were psychics. The organization used a lot of cutting-edge technology.

Most of the members of FI-6 were killed by the villain Necrom. After that, the group essentially disbanded, with its remaining agents and resources absorbed into R.C.X. (another British intelligence agency).